Electrical tire pressure gauge and indicator



L. J. KELLEN April 7, 1942.

ELECTRICAL TIRE PRESSURE GAUGE AND INDICATOR Filed July 11, 1940 2 Sheets-Sheet 1 3mm I60 JKZZerL L. J. KELLEN 2,279,140

ELECTRICAL TIRE PRESSURE GAUGE AND INDICATOR April 7, 1942.

2 Shets-Sheet 2 Filed July 11, 1940 y [In the-accompansingdrawings: 1 1 I an elevation of board indicatorjunit forming-apart of the structure ".constructedin accordance withtheinvention through a vehicle wheel the wheel unit Patented Apr. 7, i

f UVNITE-DTQSTATES;V. PATENT 0 FFICE INDICATOR Emcrmcanmn ,mssun i: GAUGE sure gauge and indicator and more especially to an electrical tire pressure gauge andindicator. The primary object oi' the invention is the provisionota device oi this character, wherein the.

instrument board within a motor vehicle presents in full view of an operator thereoi', a pressure in-:

of such vehicle dicator so that the said operator will at all times have complete knowledge oi the 7 exact pressure'condition of each pneumatic tire upon the vehicle, including the extra or spare -tire,'and will'warn or indicate when the pressure becomes dangerously low or dangerously high within the tires. v y v Another object of the invention is theprovi- Figure in an enlarged iragmentary, vertical transverse sectional view through the pressure gauge portion or the wheel unit.

7 Figure 5 is a sectional viewtaken on the line H oi Figure 4,

looking in the direction or the arrows: i t i v .Iiigure ,6 is a fragmentary vertical longiti'u'iilial sectional view through a self-adjusting brush employed in the wheel unit. v I

Figure 7 is a diagrammatic plan-view o! the V electric circuit arrangement-oi .thedevice'oonsion 01' a device of this character wherein accuracyin the working thereoi' is assured at all speeds of travel or the motor vehicle and in the installation of such device there is not required w any radical changes in the standard construction of the motor vehicle.

A further object of the invention is the provisionoi a device of this character wherein the working assembly is simple, assuring continued serviceand accuracy for determining the variable pressure conditions within the respective tires of a motor vehicle, being automatic in the operation and requires little'or no attention when installed.

stituting theinvention.

Similar reference characters indicate corresponding parts throughout the several views in the drawings. v a a Referring to the drawings in detail A designates generally a portion or a motor vehicle wheel, there being involved as usual one of such wheels fore and aft at each side of a motor velhicle (not shown), and each wheel is provided with a pneumatic tire III while under present day equipment of the motor vehicle, a spare or extra A still further object of the invention islthe provision oia device of this character which is extremely-simple in'its construction, thoroughly reliable and eflicient in the operation, enables the inflation of the tires of the'motorvehicle to the required pressure without the necessity oi the use oi. a separate hand applied gauge or those'installed with air pumps which are a part or filiing station equipment, and inexpensive to manui'acture and 1 With these and'other 'obiectsinview, the invention consists in the ieaturesoi' construction,

a being fl xed theretoin any desirable manner and iastened to the hub section tire H is carried by such vehicle in any desirable manner. Associated .with the motor vehicle. its

,wheels A and tires "and II respectivelmis the pressure gauge and indicator device including a wheel. unit B. and instrument board unit 0, re-

spectively, constituting the present invention as .will be hereinafter fully described.

Each wheel A conforms to present day con struction whereby the rim section I! is separably II, the latter having a brake. drum ll. drum ll rotates upon an axle ll asusuai, and

. within this drum ll concentric to the hub proper of said section Nisan contact ring II,

' insulated thereiromatll.

combination and arrangement or parts as will i be hereinafter more fully described, illustrated in f the accompanyingidrawings which disclose the- .prererred embodiment, oi the pointed out inthe claims hereunto'a'm e,ndled.. 1

board unit or the invention,

3 ins vertical transverseisectionalview through one of the instruments oi the instrument otthe invention applied.

invention.. a u

, Figure 2 is anenlarged detailed view phragmji. passa e 24 and to which tube 12,. cornmu'n icating or the tire II: or H-i'or The rim section," has fitting with the tire is or Ii, each includingan inner-tube II {or inviiation and deflation-in the customary manner. .Iach rim section' il carries-a casing or boiling" provided with a coupling itud' II A, ll 'ior :thelaidxrim section lirisfiitted with a fluid pressure vza'ctuated flexible, diaphragm 22 which with they I creates within the casingorboxing It; a fluid pressure chamber it for receiving fluid pressure base II a through sea en leading through the stud II and sad II for actionupon the dia-' A nipple II is threaded in this is connected a supply withthe inner tube It the flow oiiiiuid under pressure latter tothe chamber 28 to -The 'hub' section II with the jected from and fixed at II to an adjustable calibrator member support 82 which is fixed to and insulated at u on the casing or boring. The calibrator member carries a resistance orheating coil it which has electric connection with the spring contact ll through the member 34. The member 34 is urged against an adiustable calibrator screw 31 acceuible outside of the casing or boxing I! for manual adjustment. The screw 31 is insulated at a from the member 34. The member It has a iii-metal contact an insulated irom the said member 34 and engageable with the ground contact. ll, said contact ll being affected by the coil 8| iorvarying contact activity of said con hct l. with the contact TI in conformity with high or low pressure tire demands.

The drum It cover plate which is stationary about the wheel axle has fitted thereto a brush barrel ll containing a self-adjustable carbon brush it for contact with the rim It, the brush being urged against the latter by a spring, It

mums barrel II which spring is in electrical connection with an electrical lead wire M. The barrel II is adjustable at l! for variable positive 'contact of the brush with the contact ring It.

The instrument board unit C involves a plurality of indicator instruments for fluid pressure indications, one for each tire pressure and includes a casing or boxing 40 provided with a transparent front 4! for visibility of a movable indicator hand.- or point is and a fluid pressure scale or graduated marking 49 upon a dial It, the sonic or marking being traversed by the said hand or pointer ll for pressure reading purpos s i The hand or pointer. ll is'pivoted at Ii within the closing or boring and has linkage connections I2 with. a iii-metal thermo flexed arm I! fixed at I to a swingabla calibrator gear segment II which through a cog ll meshing therewith is susceptible of adiustment manually without the caaingor boxing ll at its back, so that the bi metalarln II can be regulated for a change of working condition of the same as may come abontthrmigh the use of high or low pressure pneumatic tires.

The linkage connections 52 includes a presser horn II being insulated at it from a contact point" and coacting with adjustable V-shaped spring contacts and 62, respectively, spaced from each other and at opposite sides of the contact point ll.

The contacts II and 62 are arranged in electrical connection with an electric storage battery circuit through wiring N. The contact I! when engaged with contact 8| closes the said It on the-support 82.

or markings. l! is indicative of a low pressure reading thereon.

The closing of the circuit by the said contact I. automatically illuminates a warning light signal 64 which is included in the said circuit so that an operator of the motor vehicle will have cognizance of high or low pressure conditions of the tires on the said vehicle. About the bi-metal arm 53 is a resistance or heating coil 0! which through electrical connections ti and I1, respectively. is arranged within the circuit 1), the wiring connection 28 being joined with the connection 81 for arranging the wheel unit B of the device within the said circuit D, and the ground connections for these units D and C, respectively, in this circuit are established by the body and chassis constructions of the motor vehicle.

circuit and in this position the movement or the hand or pointer 4! with relation to the scale or markings]! is indicative of a high pressure The contact 59 when engaging the contact 82 icloses the circuit through wiring I and in this position the movement of the hand or pointer 48 with relation to the scale Acting as. a pivoting base for the indicator arm ll is a leaf spring 68 which by the adjustment of a segmental gear 69 with which meshes a hand cog ll accessible from without the casing or boxing 46 at its back, can be regulated for increasing or decreasing the tensioning ac tion of the arm ll.

The spring I tensions the bi'metal arm a for varying its spring activity. The contact point I. normally moves with the bi-metal arm I! and horn II toward the contact 82 and during this movement, the hand or pointer ll traverses ihn scale or markings It in a direction for ing low pressure reading On reverse movement of the contact point I! which is brought about through the flexing of the bi-rnetal arin ll resultant from the heating of the latter by tlii heating coil ll. such movement causes the band or pointer to traverse the scale or markings I in a direction for indicating high pressure reading thereof.

Arranged within the unit C is a night lamp Ii its circuit 12 being controlled by a hand switch II included therein. This lamp II when lighted illuminates the instruments within the said instrument board unit for easy reading of the dials 0f the grouped instruments. The circult D is provided with a hand switch H so that it can be actuated by hand for the opening and closing of this circuit at will.

Each instrument of the unit C carries indicla as at I. for identifying a particular tire so that the pressure condition thereof can be ascertained. that is to say,-r. 1., which is indicative of right front tire; "I. 1.," which is indicative of left front tire; "r. r." which is indicative of right rear tire; l. r. which is indicative of It rear tire; and "spare," which is indicative of use spare'or extra tire.

From the ioregoing it Wham matan operator of the motor vehicle having the device installed therein can at a glanse with accuracy the pressure reading of air within each and all of the tires with which the motor vehicle is equipped, and particularly with regard to dangerously low or dangerously high pressure conditions of such tires. 7

It is believed that from the foregorhn. the construction and manner of operation 0! the device will be clearly understood m the requiring of a more extended explanation and therefore the latter. has been omitted. It is of course understood that changes, variations. and

modifications may be made in the device, that is in the structure set-up thereof asfall properly within the scope of the appended claims without 2. In a pressure controlled transmitter, a

departing from the spirit oi the invention or sacrificing any of its advantages.

What is claimed is:

1. In a pressure controlled transmitter, a mounting, a diaphragm carried by said mounting and responsive to a variable pressure source, a contact of an electric circuit secured to and movable with said diaphragm, a spring influenced member movably secured to and insulated from said mounting and opposing-the diaphragm, means for electrically in the electric circuit, a bi-metal contact carried by said member and coactive with the first named contact for controlling said circuit, an electric heating means for said bi-metal contact and electrically connected to said member. and an adjusting means for the member to vary the position or the bi-metal contact with respect to the first named contact.

connecting said member mounting, a diaphragm carried by the mounting and responsive to a variable pressure source, a contact of ,an electric circuit carried by the diaphragm, a member hinged on and insulated from the mounting and arranged in opposed relation to the diaphragm, tension means acting on said member to urge the latter away from the diaphragm, means electrically connecting said member to the electric circuit, a bi-metal contact carried by said member and coactivc with the first named contact in controlling the electric circuit, an electric heating element for said bi-metal contact and electrically connected to said member, and a set screw carried by said mounting and engaging the member to vary the bi-metal contact with contact.

LEO J. KELIEN.

respect to said first named 

